Morphometric analysis of gap junctions in rat myocardium after hyperkalemia.

The effect of membrane depolarization was investigated on gap junctions from isolated rat hearts perfused with a modified Krebs-Henseleit solution containing 16 mM K+. After freeze-fracturing, the configuration of the junctional particles in the ventricular myocardium was analysed by measurements of connexon densities and centre-to-centre distances between neighbouring particles. Both in control and hyperkalemic tissue, the gap junctions occur on the intercalated discs as round or oval aggregates of connexons which are closely and regularly packed in small, criss-cross-oriented arrays separated by particle-free aisles.

Complementarity of particles and pits in freeze-fractured hepatic and cardiac gap junctions.

Particles and pits of freeze-fractured gap junctions are considered as complementary structures despite the frequent observations of more regular and closer spacings of pits, ascribed to plastic deformation of particle arrays. Recently, however, the noncomplementarity of pits and particles in Purkinje fibers has been reported. To ascertain the relationship between both structures, gap junctions from fixed, cryoprotected liver and myocardium were investigated using spacing and density measurements and complementary replicas.

A modified cleansing procedure to obtain large freeze-fracture replicas.

A method for cleaning freeze-fracture replicas is elaborated which avoids their rolling up and fragmentating during successive steps. Immediately after freeze-fracturing, the replicated tissue is slowly thawed from 77 K to room temperature on solid methanol. Safe passage through the subsequent cleaning steps is facilitated by using solutions of gradually increasing surface tension.

[Comparative testing of Kamillosan cream and steroidal (0.25% hydrocortisone, 0.75% fluocortin butyl ester) and non-steroidal (5% bufexamac) dermatologic agents in maintenance therapy of eczematous diseases].

We report on 161 patients suffering from inflammatory dermatoses on hands, forearms, and lower legs who had been initially treated with 0.1% difluocortolone valerate. During the maintenance therapy carried out over a period of 3 to 4 weeks, we tested the efficacy of Kamillosan cream vs.